The present invention relates to a method for retreading and partially replacing the belt of a pneumatic vehicle tire having a radial carcass tire body, possibly accompanied by the interposition of binder layers and the use of coatings. First the replacement ply or plies, and then the finish-vulcanized, profiled tread strip, are placed upon the tire body, with the thus-built-up tire then being subjected to a pressure treatment, possibly at an elevated temperature.
In the event that a partial replacement of the belt is not required, the method that is often known as the cold topcapping method has the great advantage that for the purpose of a final processing in an autoclave or vulcanizing apparatus, the finish-overlaid tire body can be provided with a rubber sleeve that surrounds the tire body. As a result of the internal tire pressure and the pressure that exists in the vulcanizing apparatus, there then results at an elevated temperature a reliable bonding of the previously vulcanized and finish-profiled tread strip.
However, in the event that one or more belt plies also have to be replaced, the previously described simple method can no longer be used. Instead, the finish-overlaid tire must under these conditions be surrounded or enveloped by a steel bandage in order to preclude, for example, undesired shifting of the load-carrying cords of the belt, for example changes in the angular orientation of these cords.
It is therefore an object of the present invention to improve a method of the aforementioned general type in such a way that along with a relatively short vulcanizing or processing time in the vulcanizing apparatus, the aforementioned steel bandage or sleeve can be eliminated.